1. Field of the Invention
The field of the invention is data processing, or, more specifically, methods, apparatus, and products for dynamically configuring overcurrent protection in a power supply.
2. Description of Related Art
The development of the EDVAC computer system of 1948 is often cited as the beginning of the computer era. Since that time, computer systems have evolved into extremely complicated devices. Today's computers are much more sophisticated than early systems such as the EDVAC. Computer systems typically include a combination of hardware and software components, application programs, operating systems, processors, buses, memory, input/output devices, and so on. As advances in semiconductor processing and computer architecture push the performance of the computer higher and higher, more sophisticated computer software has evolved to take advantage of the higher performance of the hardware, resulting in computer systems today that are much more powerful than just a few years ago.
One area of computer technology that has seen substantial advances is power supply technology. Computer power supplies are designed to meet the maximum load expected in a given product installation. If the product has multiple option bays (e.g., PCI adapter slots or drive bays), then the power supply must be capable of powering the product with all system slots populated with devices having the maximum wattage allowed in any given slot. Furthermore, overcurrent protection is designed to shut down the outputs of these power supplies based on the maximum current output required to support a fully-loaded product. If the system slots in a product are not fully loaded, the actual maximum current requirements can be well below the capacity of the power supply, and the overcurrent protection is obviously even higher. In the case of a fault (e.g., high impedence short circuit to ground of the power supply output), there can be a large amount of reserve current capacity in the power supply in a lightly-loaded product. This “reserve” or unused current capacity (as defined by the overcurrent trip point) can continue to feed a short-circuit and cause heat build-up and eventually a fire if not detected by the user of the product. Also, in products where two or more supplies are provided to source power redundantly to a product, the reserve current can be much higher than the current required by even a maximally-configured system.